2. The laser processing pen of claim 1, wherein the optical lens is
capable of focusing a laser pulse to at least one of a circular, an
elliptical, and a rectangular cross-section

3. The laser processing pen of claim 1, wherein the at least one optical
lens has a diameter of less than about 10 mm.

4. The laser processing pen of claim 1, wherein the elongated member
further comprises at least one tape guide capable of channeling at least
a non-adhesive tape overlay in the proximity of the laser pulse exit
portion.

5. The laser processing pen of claim 1, further comprising at least one
spacer configured to create a desired space between the laser pulse exit
portion and a workpiece surface.

6. The laser processing pen of claim 1, further comprising at least one
capillary tube capable of applying a transparent overlay to at least one
of a workpiece surface, an opaque overlay, the at least one optical lens,
and the laser pulse exit portion.

7. An apparatus for laser peening a workpiece, comprising: a laser beam
source; a beam delivery system; a laser processing pen; and an overlay
application system.

8. The apparatus of claim 7, wherein the beam delivery system comprises
an articulated arm.

9. The apparatus of claim 7, wherein the laser processing pen comprises
at least one optical lens having a diameter of less than about 10 mm.

11. The apparatus of claim 7, wherein the laser processing pen comprises
at least one tape guide capable of channeling at least a non-adhesive
tape overlay along the laser processing pen.

12. The apparatus of claim 7, wherein the laser processing pen comprises
at least one spacing apparatus capable of maintaining a desired spacing
between the laser processing pen and a tape overlay.

13. The apparatus of claim 7, wherein the overlay application system
comprises an opaque overlay application system comprising at least one
automatic tape advancing device capable of advancing a tape overlay
adjacent to the laser processing pen.

14. An apparatus for laser peening a workpiece, comprising: a laser beam
source; a beam delivery system; and a laser processing pen operatively
connected to an overlay application system.

15. The apparatus of claim 14, wherein the beam delivery system comprises
an articulated arm configured to pivot about at least one axis.

16. The apparatus of claim 14, wherein the laser processing pen comprises
at least one optical lens having a diameter of less than about 10 mm.

20. The apparatus of claim 14, wherein the overlay application system
comprises an opaque overlay application system, the opaque overlay
application system comprising at least one automatic tape advancing
device capable of advancing a tape overlay adjacent to the laser
processing pen.

Description:

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority from U.S. Provisional Patent
Application No. 61/492,830, filed on Jun. 3, 2011, which is incorporated
by reference herein in its entirety.

BACKGROUND

[0003] Laser peening (also known as laser shock processing or laser shock
peening) is an innovative surface treatment for improving the fatigue
strength and damage tolerance of metal parts. Laser peening drives high
amplitude shock waves into a part surface using high intensity laser
pulses. The shock waves are used to develop deep compressive residual
stresses in the surfaces of fatigue-prone parts. Typically, these
stresses penetrate five to ten times deeper than conventional metal shot
peening. These compressive surface stresses inhibit the initiation and
propagation of fatigue cracks.

[0004] Laser peening has been particularly effective at preventing fatigue
failures in aircraft engine metal alloy fan and compressor blades.
However, the application of laser peening is much broader. The
application can encompass aerospace structures, helicopter gears and
propulsion components, automotive parts, orthopedic implants, tooling and
dies, and numerous other military and industrial parts prone to metal
fatigue failures.

[0005] Before laser peening, an overlay coating, which may be
substantially opaque to the laser beam, may be applied to the part
surface being treated. An additional layer, which may be substantially
transparent to the laser beam, may be placed over the opaque overlay. The
transparent layer may also be applied directly to the part surface,
without the application of an opaque layer. The opaque overlay may be,
for example, black paint, or tape. The transparent overlay may be, for
example, flowing water.

[0006] Suitable laser peening systems, apparatuses, and processing
conditions are disclosed in, for example, one or more of U.S. Pat. Nos.
5,741,559, 6,191,385, 6,373,876, and 7,268,317, each of which is
incorporated by reference in its entirety.

[0007] The laser pulses pass through the transparent overlay and strike
the opaque overlay, causing the opaque overlay to vaporize. The vapor
absorbs the remaining laser energy and produces a rapidly expanding
plasma plume. Because the expanding plasma is confined momentarily
between the surface of the part and the transparent overlay, a rapidly
rising high-pressure shock wave is created, which propagates into the
part. When the peak stress created by the shock wave is above the dynamic
yield strength of the metal part, the metal yields, and the metal is
"cold worked" or plastically deformed on, and just under, the surface.
This plastic deformation results in compressive residual stresses in the
surface of the part. The depth and magnitude of the residual stresses
depend upon the magnitude and rate of attenuation of the shock wave as it
passes through the surface layer, the material properties, and the
processing conditions specific to the application. Compressive residual
stresses typically extend as deep or deeper than about 0.040 to about
0.060 inches (about 1.0 to about 1.5 mm) into the surface, and can
approach the yield strength of the material.

[0008] Laser peening typically requires line-of-sight access to the
surface of the workpiece to be treated. In laser peening operations, it
is sometimes necessary to laser peen surfaces that may not be readily
processed using traditional laser peening apparatuses. For example, some
surfaces are hidden, or out of direct line-of-sight, and as such are not
able to be exposed to a laser beam generated from outside the workpiece.
Such surfaces may include, for example, inside holes, notches, grooves,
internal cavities, dovetail joints, and the like. Previous attempts at
laser peening such hidden surfaces have required the insertion of a
reflective element into the cavity adjacent to the hidden surface, and
directing a laser pulse onto the reflective element, which redirects the
pulse onto the hidden surface. However, this method requires additional
steps and, thus, additional time to laser peen hidden surfaces. What is
needed is a laser peening apparatus that is capable of accessing these
hidden surfaces and directly applying a laser pulse thereto.

SUMMARY

[0009] In one embodiment, a laser processing pen is provided, the laser
processing pen comprising: an elongated member, comprising: a laser pulse
entry portion, and a laser pulse exit portion, wherein the laser pulse
exit portion includes at least one optical lens.

[0010] In one embodiment, an apparatus for laser peening a workpiece is
provided, the apparatus comprising: a laser beam source; a beam delivery
system; a laser processing pen; and an overlay application system.

[0011] In one embodiment, an apparatus for laser peening a workpiece is
provided, the apparatus comprising: a laser beam source; a beam delivery
system comprising an articulated arm; and a laser processing pen
operatively connected to an overlay application system.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The accompanying figures, which are incorporated in and constitute
a part of the specification, illustrate various example systems, methods,
and results, and are used merely to illustrate various example
embodiments.

[0013] FIG. 1 illustrates an example arrangement of an apparatus for laser
peening a workpiece.

[0016] FIG. 1 illustrates one embodiment of an apparatus 100 for laser
peening a workpiece. Apparatus 100 includes a laser beam source 105, a
beam delivery system 110, a laser processing pen 115, an opaque overlay
application system 120, at least one pivoting device 125, and a
transparent overlay application system 130. Laser beam source 105 may be
any suitable laser beam source including, for example, those disclosed in
U.S. Pat. No. 6,373,876. In one embodiment, laser beam source 105 is a
high-repetition rate laser system.

[0017] Beam delivery system 110 may be operatively connected to laser beam
source 105. In one embodiment, beam delivery system 110 comprises an
elongated member that is at least partially hollow. In another
embodiment, beam delivery system 110 comprises an elongated member
capable of at least substantially enclosing a laser beam. In another
embodiment, beam delivery system 110 comprises an elongated member
capable of guiding a laser beam. In another embodiment, beam delivery
system 110 comprises an elongated arm member configured to pivot about at
least one axis via pivoting device 125. Pivoting device 125 may comprise
a hinge, ball and socket, joint, or any other suitable pivoting device.
In another embodiment, beam delivery system 110 comprises an elongated
arm member configured to pivot about multiple axes. For example, the
elongated arm member may be configured to pivot about one or more of the
x-axis, y-axis, and z-axis. In another embodiment, beam delivery system
110 comprises an articulated arm, configured to pivot, rotate, or both,
at a plurality of points about a plurality of axes. In one embodiment,
beam delivery system 110 comprises an elongated arm member configured to
extend or contract longitudinally, so as to increase or decrease in
length. In one embodiment, beam delivery system 110 may comprise minors
to direct a laser beam through pivoting device 125. In another
embodiment, beam delivery system 110 may comprise a fiber optic device,
including at least one fiber optic cable to direct a laser beam through
pivoting device 125. Beam delivery system 110 may be constructed from a
variety of materials, including metals, polymers, alloys, composites, and
any other suitable material.

[0018] Laser processing pen 115 may be operatively connected to beam
delivery system 110. Laser processing pen 115 may comprise an elongated
member. Various embodiments of laser processing pen 115 are disclosed
below with regard to FIGS. 2 and 3.

[0019] In one embodiment, the apparatus comprises an overlay application
system. In one embodiment, the overlay application system comprises an
opaque overlay application system, such as opaque overlay application
system 120. In another embodiment, the overlay application system
comprises a transparent overlay application system, such as transparent
overlay application system 130. In yet another embodiment, the overlay
application system comprises both an opaque overlay application system
and a transparent overlay application system. The overlay application
system may be configured to selectively apply an opaque overlay and a
transparent overlay, either simultaneously or consecutively. In one
embodiment, the overlay application system comprises a wetting fluid,
which capable of enhancing cohesion between a tape overlay and a
workpiece. In such an embodiment, the wetting fluid may be applied to
either the tape overlay, or the workpiece. In another embodiment, the
wetting fluid may be a component of either opaque overlay application
system 120, transparent overlay application system 130, or both.

[0020] Opaque overlay application system 120 may comprise any system for
applying opaque overlay, including, for example, the systems and
apparatuses disclosed in U.S. Pat. Nos. 5,741,559 and 7,268,317. In one
embodiment, opaque overlay application system 120 applies a black paint
overlay. In another embodiment, opaque overlay application system 120
applies a liquid energy-absorbing overlay that is resistant to drying and
dissolution by a transparent overlay. In one embodiment, opaque overlay
application system 120 delivers opaque overlay to the workpiece 135 via a
nozzle located in the proximity of laser processing pen 115 before
application of a laser pulse to workpiece 135. This nozzle may be
operatively connected to laser processing pen 115. In another embodiment,
opaque overlay application system 120 applies opaque overlay to workpiece
135 before laser peening. In yet another embodiment, opaque overlay
application system 120 applies opaque overlay to workpiece 135 before
application of a laser pulse to the workpiece.

[0021] In one embodiment, opaque overlay application system 120 applies a
tape overlay. In another embodiment, the tape overlay is a non-adhesive
tape overlay. In another embodiment, opaque overlay application system
120 comprises a system wherein tape overlay travels from a first reel
(not shown), to a position near laser processing pen 115 where it is
exposed to a laser beam, and onto a second reel (not shown). In this
embodiment, opaque overlay application system 120 may also comprise at
least one automatic tape advancing device (not shown) capable of
advancing the tape overlay from the first reel to the second reel. Opaque
overlay application system 120 may further comprise at least one
automatic tape advancing system configured to index the tape overlay a
short distance prior to each application of a laser pulse to workpiece
135. Further, this embodiment may also comprise at least one tape
tensioning device (not shown) capable of maintaining appropriate tension
in a tape overlay. The at least one tape tensioning device may be capable
of maintaining appropriate tension in a tape overlay when the tape
overlay is stationary, in motion, or both. In another embodiment, the at
least one tape tensioning device is capable of maintaining the tape
overlay in intimate contact with workpiece 135. For example, the tape
tensioning device might apply a tension in the tape overlay across a span
created by two or more elements of laser processing pen 115. Laser
processing pen 115 may then be positioned adjacent to workpiece 135 such
that workpiece 135 falls between, and across the plane created by, the
two or more elements of laser processing pen 115, thus forcing the tape
overlay to stay in intimate contact with workpiece 135. In another
embodiment, the first and/or second reels may be replaced with
containers, spools, or eliminated altogether. In another embodiment, tape
overlay is stored on or in any number of devices.

[0022] Transparent overlay application system 130 may apply a transparent
overlay to at least one of the opaque overlay, workpiece 135, the laser
processing pen's optical lens (described below with regard to FIG. 2), or
the laser pulse exit portion (described below with regard to FIG. 2). In
one embodiment, transparent overlay application system 130 applies a
liquid. In another embodiment, transparent overlay application system 130
applies water. In another embodiment, transparent overlay application
system 130 is operatively connected to laser processing pen 115. In one
embodiment, transparent overlay application system 130 delivers
transparent overlay to the opaque overlay, workpiece 135, the laser
processing pen's optical lens, or the laser pulse exit portion via a
nozzle located in the proximity of laser processing pen 115 before
application of a laser pulse to workpiece 135. This nozzle may be
operatively connected to laser processing pen 115. In another embodiment,
transparent overlay application system 130 applies transparent overlay to
the opaque overlay, workpiece 135, the laser processing pen's optical
lens, or the laser pulse exit portion prior to laser peening.

[0023]FIG. 2 illustrates one embodiment of a laser processing pen 200.
Laser processing pen 200 comprises an elongated member 205 which
comprises a laser pulse entry portion 210 and a laser pulse exit portion
215. In one embodiment, laser pulse entry portion 210 is operatively
connected to the beam delivery system. Laser pulse exit portion 215 may
comprise at least one optical lens 220. In one embodiment, elongated
member 205 comprises a substantially cylindrical and at least partially
hollow tube. In another embodiment, elongated member 205 may have any
suitable cross-section. In one embodiment, elongated member 205 has a
cross-sectional outside diameter of less than about 20 mm. Elongated
member 205 may be constructed from a variety of materials, including
metals, polymers, alloys, composites, and any other suitable materials.

[0024] In one embodiment, laser pulse entry portion 210 is a perforation
in elongated member 205 having a size and shape configured to allow a
laser beam to pass through uninhibited. In another embodiment, laser
pulse entry portion 210 may be a lens or window capable of transmitting a
laser beam. In one embodiment, laser pulse exit portion 215 is a
perforation in elongated member 205 having a size and shape configured to
allow a laser beam to pass through uninhibited. In another embodiment,
laser pulse exit portion 215 may be a lens or window capable of
transmitting a laser beam.

[0025] In one embodiment, optical lens 220 is capable of focusing a laser
beam such that the beam has at least one of a circular cross section, an
elliptical cross section, and a rectangular cross-section. However,
optical lens 220 may also be capable of focusing a laser beam in such a
manner as to create any cross section desired (e.g., rectangular,
including square, or hexagonal). In one embodiment, laser processing pen
200 includes a plurality of optical lenses, including at least one
spherical lens, and at least one cylindrical lens. In one embodiment, the
at least one optical lens 220 has a diameter of less than about 10 mm. In
another embodiment, the at least one optical lens 220 has a diameter
between about 2 mm and about 10 mm. In another embodiment, the at least
one optical lens 220 has a diameter between about 3 mm and about 8 mm. In
yet another embodiment, the at least one optical lens 220 has a diameter
between about 4 mm and about 6 mm.

[0026] With continued reference to FIG. 2, laser processing pen 200 may
comprise an elongated member 205 having at least a proximal end 225 and a
distal end 230. In one embodiment, laser pulse entry portion 210 is
located near proximal end 225. In another embodiment, laser pulse exit
portion 215 is located near distal end 230.

[0027] In one embodiment, elongated member 205 comprises at least one tape
guide 235. In one embodiment, at least one tape guide 235 is configured
to channel at least a tape overlay. In another embodiment, at least one
tape guide 235 is configured to channel at least a non-adhesive tape
overlay. In another embodiment, at least one tape guide 235 is configured
to channel at least a tape overlay in the proximity of laser pulse exit
portion 215. At least one tape guide 235 may be operatively connected to
elongated member 205, and configured to channel a tape overlay
longitudinally along the exterior of elongated member 205. In one
embodiment, at least one tape guide 235 is configured to guide tape
overlay from proximal end 225 of elongated member 205 to distal end 230
of elongated member 205 and between laser pulse exit portion 215 and a
workpiece surface. In yet another embodiment, at least one tape guide 235
is configured to channel tape overlay continuously along elongated member
205, around distal end 230, and between laser pulse exit portion 215 and
a workpiece surface. In another embodiment, the tape overlay is advanced
through at least one tape guide 235 along elongated member 205 by an
opaque overlay application system comprising at least one automatic tape
advancing device.

[0028] In one embodiment, elongated member 205 comprises at least one
spacing apparatus 240. In one embodiment, the at least one spacing
apparatus 240 is located in the proximity of laser pulse exit portion
215. In another embodiment, at least one spacing apparatus 240 is
configured to create a desired space between laser pulse exit portion 215
and a workpiece surface. In one embodiment, spacing apparatus 240
includes at least one spacer, which can include any device capable of
maintaining a particular desired spacing, a maximum spacing, or a minimum
spacing between elongated member 205 and the workpiece. For example, the
at least one spacer can be configured to: maintain a desired spacing
between laser pulse exit portion 215 and the workpiece surface, maintain
a desired spacing between laser pulse exit portion 215 and a non-adhesive
tape overlay, or both. In one embodiment, spacing apparatus 240 includes
at least one spacing ball configured to offset tape overlay away from
laser pulse exit portion 215 at an appropriate distance, or range of
distances. The at least one spacing ball may be integrated into elongated
member 205. In another embodiment, tape overlay is channeled between the
at least one spacing ball and a workpiece surface. The at least one
spacing ball may provide a low-friction surface over which a tape overlay
may be channeled. In one embodiment, the at least one spacing ball is a
ruby ball. In another embodiment, the at least one spacing ball is biased
away from elongated member 205 and toward a workpiece surface. Biasing
may be achieved through the use of any biasing device commonly understood
in the art, including without limitation a spring. In another embodiment,
the at least one biased spacing ball is configured to keep an opaque
overlay in intimate contact with a workpiece surface during laser
peening. In one embodiment, at least one spacing apparatus 240 may be
positioned between laser pulse exit portion 215 and proximal end 225. In
another embodiment (not shown), at least one spacing apparatus 240 may be
positioned between laser pulse exit portion 215 and distal end 230. In
yet another embodiment (not shown), a plurality of spacing apparatuses
240 may be used, and positioned both between laser pulse exit portion 215
and proximal end 225, and between laser pulse exit portion 215 and distal
end 230.

[0029] Elongated member 205 may further comprise at least one capillary
tube 245 configured to deliver a liquid, such as a transparent overlay,
onto at least one of optical lens 220, the opaque overlay, laser pulse
exit portion 215, and the workpiece surface. As described above in
reference to FIG. 1, a transparent overlay may be applied to one or more
of optical lens 220, opaque overlay, laser pulse exit portion 215, and
workpiece surface during laser peening. In one embodiment, at least one
capillary tube 245 may be operatively connected to the transparent
overlay application system (described above in reference to FIG. 1). In
one embodiment, at least one capillary tube 245 may be integrally
incorporated into elongated member 205. In another embodiment, at least
one capillary tube 245 is configured to deliver a liquid to the surface
of at least one optical lens 220 to flush debris and bubbles therefrom.
In another embodiment, at least one capillary tube 245 is configured to
deliver a liquid to the surface of at least one optical lens 220 to
protect optical lens 220 from debris ejected from the workpiece surface.
In another embodiment, at least one capillary tube 245 is configured to
deliver a liquid, such as transparent overlay, to the opaque overlay
prior to laser peening. In another embodiment, at least one capillary
tube 245 is configured to deliver a liquid to laser pulse exit portion
215 to flush debris therefrom. In yet another embodiment (not shown), a
plurality of capillary tubes 245 are employed, configured to deliver a
liquid onto one or more of optical lens 220, the opaque overlay, laser
pulse exit portion 215, and the workpiece surface.

[0030]FIG. 3 illustrates another example embodiment of a laser processing
pen 300. Laser processing pen 300 is similar to laser processing pen 200
illustrated in FIG. 2. Like components are referred to by like reference
numerals.

[0031] In this example embodiment, elongated member 205 includes multiple
tape guides 235 about its periphery. Elongated member 205 further
comprises a plurality of spacing apparatuses 240 positioned on either
side of laser pulse exit portion 215. Laser processing pen 300 further
comprises a tape overlay 305, channeled through tape guides 235, and
between spacing apparatuses 240 and a surface of a workpiece 315. In one
example embodiment, tape overlay 305 advances from a first reel of opaque
overlay application system (not shown), through tape guides 235, and onto
a second reel of opaque overlay application system (not shown). In
another embodiment, at least one tape tensioning device (not shown) may
be utilized to maintain a desired tension in tape overlay 305 as it
traverses through tape guides 235.

[0032] With continued reference to FIG. 3, a laser pulse 310 is
illustrated traveling through laser pulse entry portion 210 and into one
or more optical lens 220, which redirects laser pulse 310 out laser pulse
exit portion 215 and onto tape overlay 305.

[0033] With regard to FIGS. 1, 2, and 3, in one embodiment, the apparatus
100 as described above is employed in a method for laser peening a
workpiece, wherein apparatus 100 is selectively positioned in reference
to the workpiece. Laser processing pen 200, 300, as described above is
positioned such that the at least one optical lens 220 and laser pulse
exit portion 215 are adjacent to a workpiece surface with a desired
spacing. Such desired spacing may be maintained by one or more spacing
apparatuses 240. After laser processing pen 200, 300 are in a desired
position, opaque overlay application system 120 applies an opaque overlay
between at least one optical lens 220 and the workpiece surface. Upon
application of an opaque overlay, a laser pulse from laser beam source
105 is directed along beam delivery system 110, into laser processing pen
200, 300, and onto the workpiece surface.

[0034] In another embodiment, the method for laser peening a workpiece
further comprises application of a transparent overlay via transparent
overlay application system 130 and capillary tube 245 at least between
the at least one optical lens 220 and the opaque overlay. In another
embodiment, the method further comprises applying a transparent overlay
via transparent overlay application system 130 to the surface of at least
one optical lens 220. Such application of transparent overlay to the
surface of at least one optical lens 220 may act to wash debris from the
surface of the optical lens, remove contaminants from the air between the
optical lens and the workpiece, or both. In yet another embodiment, the
method comprises applying a transparent overlay via transparent overlay
application system 130 to one or more of laser pulse exit portion 215 and
a workpiece surface to clear contaminants or obstructive particles from
the same.

[0035] In another embodiment, opaque overlay application system 120
utilized in the method applies a tape overlay 305 and further comprises
at least one automatic tape advancing device (not shown), capable of
automatically advancing tape overlay 305 adjacent to laser processing pen
200, 300 during laser peening. In another embodiment, the method further
comprises the step of advancing tape overlay 305 between at least one
optical lens 220 and a workpiece surface. In still another embodiment,
opaque overlay application system 120 comprises at least one tape
tensioning device (not shown) and the method further comprises the step
of maintaining appropriate tension in tape overlay 305 during laser
peening.

[0036] With continued reference to FIGS. 1, 2, and 3, in one embodiment
the method further comprises the step of advancing tape overlay 305 along
elongated member 205 though at least one tape guide 235. In another
embodiment, laser processing pen 200, 300 includes at least one spacing
apparatus 240, which maintains desired spacing between at least one
optical lens 220 and the workpiece surface. In another embodiment, at
least one spacing apparatus 240 is configured to maintain desired spacing
between at least one optical lens 220 and tape overlay 305. In yet
another embodiment, at least one spacing apparatus 240 is configured to
press tape overlay 305 into intimate contact with the workpiece surface,
in at least the proximity of laser exit portion 215, such that tape
overlay 305 intimately contacts the workpiece surface when a laser pulse
is applied to tape overlay 305.

[0037] In one embodiment, a method for laser peening a workpiece comprises
the steps of positioning laser processing pen 200, 300 such that at least
one optical lens 220 and laser pulse exit portion 215 are adjacent to a
workpiece surface, with a desired spacing between laser pulse exit
portion 215 and the workpiece surface maintained by one or more spacing
apparatus 240. This method further comprises the positioning of tape
overlay 305 between one or more spacing apparatus 240 and the workpiece
surface, such that one or more spacing apparatus 240 maintains tape
overlay 305 in intimate contact with the workpiece surface. Upon
positioning laser processing pen 200, 300 as described, a laser pulse 310
is generated by laser beam source 105, directed along beam delivery
system 110, into laser processing pen 200, 300, through at least one
optical lens 220, and onto tape overlay 305. Following delivery of this
laser pulse, opaque overlay application system 120 advances tape overlay
305 a specified distance using a tape advancing device (not shown) while
maintaining a desired tension in tape overlay 305 using a tape tensioning
device (not shown). This advancing of tape overlay 305 is configured to
present a portion of tape overlay 305 that has not been previously
exposed to laser pulse 310, and wherein tape overlay 305 continues to be
pressed into intimate contact with the workpiece surface by one or more
spacing apparatus 240. In this embodiment, opaque overlay application
system 120 advances tape overlay 305 by indexing tape overlay 305 a
desired distance between laser pulses. In another embodiment, opaque
overlay application system 120 continuously advances tape overlay 305 at
a desired rate, which may be constant or near-constant. In another
embodiment, the method may further comprise the step of applying a
transparent overlay from transparent overlay application system 130 and
through at least one capillary tube 245, immediately before application
of laser pulse 310. In another embodiment, transparent overlay
application system 130 applies the transparent overlay after application
of laser pulse 310. In yet another embodiment, transparent overlay
application system 130 applies the transparent overlay constantly before,
during, and after application of laser pulse 310.

[0038] Unless specifically stated to the contrary, the numerical
parameters set forth in the specification, including the attached claims,
are approximations that may vary depending on the desired properties
sought to be obtained according to the example embodiments. At the very
least, and not as an attempt to limit the application of the doctrine of
equivalents to the scope of the claims, each numerical parameter should
at least be construed in light of the number of reported significant
digits and by applying ordinary rounding techniques.

[0039] Notwithstanding that the numerical ranges and parameters setting
forth the broad scope of the invention are approximations, the numerical
values set forth in the specific examples are reported as precisely as
possible. Any numerical value, however, inherently contains certain
errors necessarily resulting from the standard deviation found in their
respective testing measurements.

[0040] Furthermore, while the systems, methods, apparatuses, and so on
have been illustrated by describing example embodiments, and while the
example embodiments have been described and illustrated in considerable
detail, it is not the intention of the applicant to restrict, or in any
way, limit the scope of the appended claims to such detail. It is, of
course, not possible to describe every conceivable combination of
components or methodologies for purposes of describing the systems,
methods, apparatuses, and so on provided herein. Additional advantages
and modifications will readily appear to those skilled in the art.
Therefore, the invention, in its broader aspects, is not limited to the
specific details and illustrative embodiments shown and described.
Accordingly, departures may be made from such details without departing
from the spirit or scope of the general inventive concept. Thus, this
application is intended to embrace alterations, modifications, and
variations that fall within the scope of the appended claims. The
preceding description is not meant to limit the scope of the invention.
Rather, the scope of the invention is to be determined by the appended
claims and their equivalents.

[0041] Finally, to the extent that the term "includes" or "including" is
employed in the detailed description or the claims, it is intended to be
inclusive in a manner similar to the term "comprising," as that term is
interpreted when employed as a transitional word in a claim. To the
extent that the term "operatively connected" is employed in the detailed
description or claims, it is intended to mean that the identified
components are connected in a way to perform a designated function. To
the extent that the term "selectively" is employed in the detailed
description, it is intended to identify a condition of a component
wherein an operator of the apparatus or software configured to control
the apparatus may activate or deactivate the feature or function of the
component as is necessary or desired in use of the apparatus.
Furthermore, to the extent that the term "or" is employed in the claims
(e.g., A or B) it is intended to mean "A or B or both." When the
applicants intend to indicate "only A or B, but not both," then the term
"only A or B but not both" will be employed. Similarly, when the
applicants intend to indicate "one and only one" of A, B, or C, the
applicants will employ the phrase "one and only one." Thus, use of the
term "or" herein is the inclusive, and not the exclusive use. See Bryan
A. Garner, A Dictionary of Modern Legal Usage 624 (2d. Ed. 1995).